Hydraulic press control



May 30, 1944.

P. c. COLLINS HYDRAULIC PRESS CONTROL Filed June 17. 1940 5 sheets sheeg1 Paul. C. C OLLINS ATTORNEY May 30, 1944. P. c. COLLINS HYDRAULIC PRESSCONTROL Filed June 17, 1940 5 Sheets-Shoat 2 0 2 6 [ll -1- I m TI: \.i xm 4 6 3 5 5 l a 7 3 w 2 a 2 4 2 I 5 3 7 2 4 3 6 2 6T INVENTOR PRUL C.COLLINS ATTORNEY May 30, 1944. P. c. COLLINS 2,350,217

HYDRAULIC PRESS CONTROL Filed June 17, 1940 5 Shegts-Sheet 3 O INVENTORPAUL C. C OLLINS mmzwuc rnnss conwnoz. 7

Filed June 17. 1940 5 sheets-sheet 4 ueuml INVENTOR PnuL C. COLLINS 21/4g g A'ITORNEY Patented May 30, 1944 HYDRAUIJOPBESS CONTROL Panic.Collins, Norwood, Pa., assignor to The Baldwin Locomotive Works,

Pennsylvania a corporation of Application June 11, 1940, Serial No.341,046

8 Claims.

This invention relates generally to hydraulic presses and moreparticularly to improved control means therefor.

The hydraulic press shown herein is of the customary type having amovable platen operated by a main cylinder and ram and by pullback rainsand cylinders, the fluid pressure being supplied alternatively to saidcylinders from any suitable source such as a reversible hydraulic pumpwhich is shifted selectively to its forward pressure position, to itsreversing pullback position or to its neutral position to hold themovable platen in its uppermost position, or, if desired, fluid pressuremay be supplied from a continuous source such as a uni-directionaldischarge pump or from an accumulator system in which cases fluidpressure is alternatively supplied to the main and pullback cylindersthrough a well-known reversing valve. This reversing valve and itssource of pressure are equivalent to the fluid distributing function ofthe reversible pump mechanism although a reversible pump is shown hereinfor the purpose of illustration.

One object of the present invention is to provide an improved cammechanism for controlling and shifting the fluid distributing means,

this cam mechanism being operated in synchronism with the platenmovements. A further 'object is to provide an improved cam mechanismwhereby the timing of the movements of the press platen, such as theupper and/or lower limits of travel of the platen, may be individuallyor relatively varied with accuracy, dispatch and convenience, preferablywhile the press is in continuous operation.

Another object is to provide an improvedvolumetric control for thepumping mechanism, this control being applicable during either thepressing or return stroke although duplication of the control adapts itto both strokes.

A further object is to provide an improved cam control mechanism inwhich the timing of the press controlled events are indicated on asuitable indicating mechanism that is instantly' and continuouslyvisible to the operator. Another object is to provide an improvedvariable cam control mechanism that is relatively simple inconstruction, operation and maintenance and is compact and durable andhas a high degree of sensitivity, accuracy and ease of operation, aswell as being conveniently accessible to an operator at all times.

Other objects and advantages will be more lowing description of theaccompanying drawings in which:

Fig. 1 is a diagrammatic illustration of my invention applied to a presswhich is only partially shown;

Fig. 2 is a vertical section of my improved cam control mechanism takensubstantially on the lines 2-2 of Figs. 3 and 4; 1

Fig. 3 is a plan view of Fig. 2 but omitting the cam lobes for purposesof clarity;

Fig. 4 is a transverse section taken substantially on the lines 4-4 ofFigs. 2 and 3;

Fig. 5 is a front elevation of Figs. 2 and 3 viewed from the left sidethereof and Figs. 6, '7 and 8 are transverse section taken respectivelyon the lines 6-8, 1-1 and 8-8 of Fig. 2.

In the particular embodiment of the invention such as is disclosedherein merely for the purpose of illustrating one specific form amongpossible others that the invention might take in practice, I havediagrammatically illustrated in Fig. 1 one side of a hydraulic presshaving a base or stationary platen I joined by columns 2 to an upperstationary crosshead 3. The press is, of course, preferablysymmetrically arranged but its details of construction do not enter intothe present invention. A movable platen 4 is moved'downwardly during apressing stroke by any suitable number of main rams and cylinders oneset of which is generally indicated at 5 and is returned to itsupperposition by usual pullback rams and cylinders generally indicated at 6.As is customary with hydraulic presses of this type during the initialportion of the pressing stroke pressure fluid is supplied to the maincylinders 5 from a usual filling tank (not shown) communicating throughany suitable filling valve diagrammatically indicated at 1. Afterfilling of the main cylinders with low pressure fluid during the initialportion of the pressing stroke the filling valve then closes and fluidunder high pressure is supplied to the main cylinders from a pumpdiagrammatically indicated at 8, Fig. 1. This pump is to be consideredfor purposes of illustration as of the well-known variable positivedisplacement Hele-Shaw reversible type having uni-directional rotationdriven by a suitable motor 9. Fluid pressure from this pump isalternatively supplied to the main and the pullback cylinders 5 and 6.For purposes of diagrammatic illustration, the pump is shown asconnected to the main and the drawback cylinders by pipes l0, althoughit will, of course, be

apparent to those skilled in the art from the folunderstood that usualrelief valves, by-pass about three-fourths of a turn. The cam mech--anism controls the up and down movements of a rod l which is connectedthrough a suitable bell crank l5a to a usual pump servo-motordiagrammatically indicated at I517. The cam mechanism, linkages and pumpare shown in Fig. l in their neutral position. When the rod l5 movesupwardly the pump 3 is shifted so as to supply operating fluid to themain cylinders 5 for a pressing operation whereas when the rod I5 ismoved downwardly the pump 3 is shifted to the other side of its centerso as to supply operating fluid to the pullback cylinders 3 and drawfluid from the main cylinders. Excess or make-up fluid during either ofthese operations is taken care of by usual communication with thefilling tank. The gear rack ll, Fig. 3, is prevented from rotating by aremovable pin ll.

, The cam mechanism for controlling the distribution of operating fluidcomprises, Fig. 2, a cam supporting disc l3 keyed to a sleeve I! whichis journalled upon an inner sleeve l3, this latter sleeve being keyed asat- I! to shaft l3. Shaft I3 is Journalled in bearings 23 and 2| of asuitable stationary frame 22 mounted preferably at a convenient frontportion of the frame. A second cam supporting disc 23 is journalled uponthe disc sleeve H. A worm gear 24 is keyed at 23 to a hub of disc 23while a similar worm gear 23 is keyed at 2'! to sleeve H of the othercam disc l3. An outermost disc 23 is keyed as at 33 to sleeve l3 and issecured .to shaft I3 through key l3. The sleeve and disc arrangement sofar described is held in axial position by a nut 3| threaded on shaft l3and engaging sleeve I 3, while an inner nut 32 threaded on sleeve l3engages disc 23. To either adiust.or hold the cam discs l3 and 23 in apredetermined angular relation to each other and to the shaft I3, Iprovided a worm 33 meshing with worm gear 24 and transversely journalledin a suitable bracket 35 which is secured to the rear side of front disc23 for bodily rotation therewith. A similar worm 33 meshes with wormgear 23 and is transversely journalled in a bracket 31 which also issecured to disc 23 for bodily rotation therewith. To rotate the worm 33there is provided, as shown in Fig. 4, a pair of bevelled gears 33secured respectively to worm 33 and to a shaft 33 which is journalled indisc 23, the front end of shaft 33 being provided with a hand grip 43.Similarly, the other worm 33 is provided with a pair of bevelled gears4| whose axial shaft 42 is also journalled in disc 23 and provided witha hand grip 43. By manually rotating either or both of the knurled grips43 and 43, the cam discs l3 and 23 may be relatively angularly adjustedthereby adjusting the extent of movements of the press platen ashereinafter described. To indicate the positions of the cam discs thereis provided, as shown in Fig. 4, small worm gears 45 and 43 securedrespectively to the worms 33 and 33 so as to rotate therewith. Smallworm gears 41 and 43 mesh with the worms 43 and 43 and are suitablyJournailed in the brackets 33 and 31 which are secured to the back sideof disc 23. The worm gears 41 and 43 are mounted upon shafts whichextend through disc 23 and carry on their outer face index dials 33 and3|, Fig. 5, suitably graduated so that the angular position of the camdiscs l3 and 23 may be indicated by suitable pointers-32 secured to thefront face of disc 23.

The cam disc I3 is provided with a pump neutralizing cam lobe 33 securedin any desired fixed angular position with respect to disc 13 by bolts34. A pair of cam lobes 33 and 33 is similarly secured to the seconddisc 23 as by bolts 51 and 53. To have the cam'lobes operate control rodl5, this rod is secured to a vertically movable crosshead 33 which isslidably guided in a crosshead guide 3| formed in the forward portion offrame 22 and provided, as shown in Figs. 3 and 5, with guide gibs 32 and33. As shown'in Fig. 2, crosshead 33 has a shaft 34 extendingtherethrough and firmly held by an enlarged collar portion 33 and a nut33. A pair of cam follower rollers 31 and 33 are journalled upon theouter ends of shaft 34. Rigidly secured to the lower end of crosshead 33is a similar roller shaft 33 provided with a third cam follower roller13. v

To manually shift the pump to any one of its three positions, namely,forward, neutral-or reverse, there is shown in Fig. 5 a hand lever 12pivoted at 13 in a suitable stationary bracket 14 15 bearing against theunder side of pin 13, Fig.

2, it being understood that the weight of rod l3 and crosshead 33 biasesthe crosshead and its pin 13 downwardly. To keep the hand lever 12 in anormally inactive relation 'to pin 13, a weight 11. Fig. 5. is pivotallyconnected by a rod 13, Fig. 2, to the bifurcated end of arm 13. The handlever is thus normally maintained in its upper position 1211, Fig. 5.The frame 22 is supported on any suitable stationary part of the pressframe or other stationary structure diagrammatically indicated in Fig. 2at 13.

' To adjust the volumetric displacement of the pump, I provide an arm33, Fig. 2,. pivoted at 3| to a stationary bracket 32. This arm has apin. and slot connection 33 with a nut 34 which is non-rotatably butslidably supported on the base- 35 of bracket 32. An axially fixed screw33 is threaded in nut 34 and has a hand grip 31 whereby rotation of thescrew in either direction causes the nut 34 to move arm 33 upwardly ordownwardly within a slot 33 of crosshead 33. To obtain any desiredvolumetric displacement of the pump for use on the pressing stroke andthereby determine the rate of pressing speed, the arm 33 is adjusteddownwardly to a predetermined point at which it serves as a limit stopfor the lower end 33 of crosshead 33. This limits the upward movement ofthe crosshead 33 beyond its neutral position and accordingdy limitsthevolumetric displacement of the pump, it

being understood that the slot 33 is of sufilcient height that the'arm33 may be adjusted upwardly to a point giving maximum volumetricdisplacement without having the upper end of the slot strike the arm. Itwill be understood that arm 30 is spaced from the lower end of slot 23when pump neutralizing cam 33 is in engagement with roller 61 and hencethis space allows crosshead 39 and pump rod Ilto be moved upwardly awayfrom cam 33 to shift the pump of! of neutral to its forward or pressingposition until lower end 39 strikes arm 30. Hence theextent to which thepump may be shifted wardly biasing but yieldable force of thrust orsolenoid I29.

in its forward position to determine its volumetric displacement iscontrolled by the ad- .iustment of .arm 90. I

,'As shown in Fig. 5, three llm'tswitches diagrammatically indicated atI Is. In and m, provided respectively with pivotal actuating arms III,I39 and I34 are suitably mounted upon a portion of thestationary frame22 or 39. These switch arms are actuated by various cams mounted uponcertain of the cam discs, shown in Fig. 2, to be describedin connectionwith the operation of the equipment.

Operation The mode of operation of my improved cam mechanism will bemore readily understood when described in connection with the controlcircuit of Fig. 1 which, for purposes of illustration, is of theelectrical type.

The cam control of Fig. 2 and the circuit in Fig. 1 are shown in neutralwith the press platen stopped in its upper postionwherein a switch H5 isclosed by cam I6 thereby establishing a circuit from a current source II5 through a solenoid Ill and a line H3, across a closed switch 9 and aline I to the other side of the current supply 8. Energization ofsolenoid'ill closes two swtches I2I and I22. The operator can nowinitiate down movement of platen 4 by closing a palm switch I23 wherebycurrent is supplied from source IIB, thence through wire I24. acrossswitches I2I, I23 and wire I25 to athrustorsoienoid I29 and thence backto the other side of the current supply IIB. Upon closure of palm switchI23, the switch II 9 is simultaneously opened to insure a single cyclecontrol to be described later.

However, opening of switch I I9 does not interrupt the current for relaysolenoid 1 because the circuit therefor connects from wire H3 across 9switch I22 and wire I2'I to the other side of the current supply.Energization of solenoid I29 shifts the pump 9 to its full forwardpressing pos tion, fluid being discharged from the pump to the maincylinders 5. It is desirable to have the operator keep his hands on thepalm switch I23 so as to avoid injury during down movement of the pressbut when the press has moved down sufliciently so as to close the diesit is permissible for the operator to take his hands off of the palmswitch I23. To do this it is necessary to maintain the solenoid I29energized which is done by For reversing the' press in accordance withpressure, a pressure responsive switch "I opens automatically inresponse to a-predetermined main cylinder pressure. Opening of thisswitch automatically de-energizes thrustor solenoid I29 thereby allowingthe weight of rod I6 and associated parts to shift the pump to itsreverse position and thus supplyfiuid to the pullback cylinders 3. RodI3 and crosshead 30 move downwardly until roller 63, Fig. 2, engages thecam 33, this cam limiting the extent of downward movement of roller 68so that the-pump effects only a very restricted rate of reverse pressmovement if at'all. If a rubber pad or other resilient-means isinterposed between the pressplatens as is ,re-

quired in some operations. then the foregoing restricted pump reversalavoids a sudden rebound of the movable press platen upon release ofpressure in the main cylinder. For instance if the cam 58 is adjusted togive a very restricted press reversal, the resilient force will becontrolled to' allow only agradual upward movement of the a cam 23'closing a switch I30 placed in parallel downwardly so as to partiallyreduce the pump stroke and thereby slow down the press speed. Thispartial down movement is against the uppress and even though th s is fora'short distance it will be sufficient to rotate disc 23 and hence movecam 56 out of the path of roller 39. This roller will thereupon dropuntil the roller engages the periphery of disc 23 and thus allow thepump to move past its neutral position and into reverse so as to supplyoperating fluid to the pullback cylinders and move the press upwardly.when the main cylinder pressure initially drops, the pressure responsiveswitch I3I immediately recloses but this will not allow re-energizationof relay solenoid I" because top position switch 5 has been previouslyopened on the initial down stroke. The press w ll therefore continueupwardly until neutralizing cam 53, Fig. 2, engages roller 61 and shiftsrod I5 and-thep'un'ip back to their neutral position thereby bringingthe press to a stop. Substantially simultaneously with shifting of thepump to neutral, cam '13 closes switch I I 5 but reclosure of thisswitch does not cause the press to restart on its down stroke eventhough closure of switch H5 re-energizes relay solenoidl I1 and closesswitches HI and I22. The reason why closure of switch I2I does notre-energize thrustor solenoid I29 is because palm switch I23 is presumedto be open and also switch Safety single cycle control.--If the operatorfails to take his hands off of palm switch 423 during .retum movement ofthe platen, stll the press will not restart on its down stroke afterreturning to its upper position for the reason that switch H9 isconnected to switch I23 and is open when'switch I23 is closed. Hence, solong as switch I I9 is openrelay solenoid II'I cannot be reenergizedeven though switchi II! is reclosed when the press returns to its upperposition. Therefore, with solenoid II1 de-energized, the switch I2Icannot reclose and the circuit through the now assumed closed palmswitch I23 is fully broken. Hence, energization of solenoid I" requiresclosure of both switches I I5 and II 9. However, if the operator removeshis hand from palm switch I23, then switch II9 will close thereuponre-energizingrelay III to close switches I2I and I22. Thereupon theoperator can reclose palm switch I23 to energize thruster solenoid I29to start the next down cycle.

Position reversaL-A normally closed switch I33 is provided with a switcharm I34 adapted to be engaged by a cam 29' when the press platen reachesa predetermined lower position. Opening of switch I33 breaks the controlcircuit in the same manneras opening of the pressure responsive switchI3I. 'It will be understood that when pressure reversal is employed thepositioning switch is maintained closed preferably by removing theposition reversal cam. Conversely, when position reversal is employedthe pressure reversal switch I3I is maintained closed preferably byclosing the fluid pressure pipe thereto.

To obtain full automatic operation wherein the press moves up and downwithout stopping, it is only necessary to maintain a continuously closedcircuit across switches I I 9 and I23, this being accomplished by theprovision of by-pass circuits I35 and I35 both of which would be closedby manual switches I31 and I33. Circuit I 36 is also provided with aswitch I39 which is closed by a solenoid I40, this solenoid beingenergized upon momentary closure of a manual switch I. Energization ofthis solenoid then closes a holding circuit I42. Switch I39 remainsclosed so long as there is no emergency stop of the' press. Hence, whenthe press moves to its upper position to close top limit switch I I5, acircuit is immediately established for energizing relay solenoid II'Ithereby to close switch I2I which establishes a circuit for thrustorsolenoid I29 to shift the pump to its forward pressing position. At thelower position of the press it is reversed in accordance with apredetermined condition of operation brought about either by positionreversal or pressure reversal through switches I3I or I33. Hence, thepress will move continuously up and down.

Emergency stopping and return of the press at any point during itspressing stroke during semi-automatic operation (one complete pressingand return cycle only) is accomplished merely by momentarily opening aswitch I43 which thereupon breaks the circuit for relay solenoid III sothat switches I2I and I22 open. The pump then is automatically shiftedto its reverse po-v sition to move the press upwardly, the press comingto a stop at its uppermost position by action of cam 53 moving the pumpto neutral. The press can then be restarted merely by closing palmbutton I23. During full automatic operation the same emergency switchcan be employed.

However, to restart the press operation it is necessary to momentarilyclose switch I to re- 'energize solenoid I4II thereby to close-switchI39 and re-establish the by-pass circuit I35.

To stop the press in any desired position during the down stroke withouthaving the press then move upwardly, it is only necessary to shift thepump to its 'neutral position, this being accomplished by closure of aswitch I44 which closes a circuit I 45 for energizing a neutralizingthruster specifically shown herein for the purpose of illustration inthe form of a solenoid I45. The solenoid I45 engages the lever of. bellcrank I54: and is able to move the same upwardly only to its neutralposition. To restart the cycle the switch I44 is opened thereby causingthe weight of rod I and associated parts to shift the pump to itsforward pressing position.

-Ope1'a1.ion--cam adjustments The present invention has particularreference gree of accuracy together with providing an ar .rangement thatis sturdy and compact so that it may be installed in a remote controlstand separate from the press structure per se if so desired. Thisadjustment can be eiiected either during operation of the press or whilethe same is at rest. To make such adjustments, for example to vary theposition neutralizing cam 53, Fig. 2, and thereby determine the topposition of the press platen, it is only necessary for theoperator tomanually rotate knob 43 which rotates shaft 42, bevel gears 4 I, wormand worm gear 25 thereby causing a key 21, Fig. 2, to rotate sleeve IIwhich in turn rotates cam disc I5 and accordingly angularly adjusts theposition of neutralizing cam 53. Similarly, to adjust the position ofslow draw stroke cam 55, as well as cam 55 which allows initialresilient reversal-of the press platen by virtue of a rubber pad orother means, the operator manually adjusts knob 40, Fig. '3, which, asshown in Figs. 2 to 4, rotates shaft 39, bevel gears 38, worm 33 andworm gear 24 thence through key 25 causing rotation of cam disc 23 andcams 55 and 59. The foregoing cam adjustments are indicated on the-faceof front disc 29 by indexed dial discs 50 and 5I, Figs. 2 and 5,connected to the adjusting mechanisms for discs I8 and 23 through asmall worm and worm gear shown in Fig. 4 at 45, 41 and at 45, 48.Suitable pointers 52, Fig. 5, have a normally fixed position withrespect to disc 29 thereby to indicate the angular position on the dials50 and 5| A position reversal cam 29', Fig. 2, may be remov ably boltedto disc .29 at any desired angular position thereon thereby determiningthe position at which the press platen is reversed. To allow for suchadjustment a series of angularly spaced bolt holes I05, Fig. 4, may beplaced around the disc circumference.

During operation of the press it will be understood that the-cam discsI9, 23 and 29 have a continuous back and forth movement, specifically anoscillating movement, in synchronism with movement of the press platen.During such oscillating movement it is possible for the operator tograsp handle or 43, rotate the same for adjusting the discs I5 and 23thereby permitting the operator to observe the extent of platen movementand its immediate eflects in response to the cam adjustments. In thisway no time is lost and all mechanical elements are in continuousoperative relation without any need of making disconnections or othertime consuming or expensive adjustments.

The eifectiveness'with which my improved cam mechanism is adapted to bebrought into compact relationship to position reversal switch I33, topposition switch H5 and switch I30 while allowing the operator to removehis hands from palm switch I33is seen in Fig. 5 wherein these switchesare conveniently spaced around the disc 29.

Also brought into compact cooperative relationship to the cam operatedcrosshead 60, Fig. 2,

is my improved .pump volume control 8II5'I whereby the operator withoutchanging his position with respect to the cam control mechanism maymanually rotate handle 81, Fig. 2, thereby swinging arm 30 upwardly ordownwardly to pro vide a limit stop for upward movement of crosshead 59through engagement of lower portion 89 thereof with arm 80. The extentof upward movement of crosshead 60 determines the extent of eccentricityof the Hele-Shaw type of pump thereby controlling the rate of dischargeor volume from the pump. Such volume control in turn determines the rateof movement of the press platen. In addition to this convenientvolumetric control, I have also brought into cooperative control withthe crosshead 60 but without interfering with the cam or volume controlsa manual operating lever 12, Figs. 2 and 5, whereby by swinging lever 12downwardly to position 12a the short arm 15 of the lever engages pin 16,Fig. 2, to raise crosshead 60 and thereby effect a pressing operation,whereas by moving lever 12 to position 12b, Fig. 5, the lever arm 15permits the weight of crosshead 60 and rod l5 to move said elementsdownwardly thereby reversing the pump and sending the press platento itsupper position.

From the foregoing disclosure it is seen that I have provided anextremely simple, effective and sturdy control mechanism having a highdegree of flexibility of operation with maximum compactness andconvenience, together with accuracy and sensitivity.

It will of course be understood that various changes in details ofconstruction and arrangement of parts maybe made by those skilled in theart without departing from the spirit of the u invention as set forth inthe appended claims.

I claim:

1. A control apparatus for a hydraulic press comprising, in combination,an oscillatable shaft, a plurality of cam discs-Journalled coaxially ofsaid shaft to have oscillating movement therewith and each beingindependently adjustable relative thereto and to each other, a pluralityof members arranged concentrically with respect to each other and tosaid shaft for adjusting said cam discs, and means whereby saidplurality of concentric members oscillate at all times as a normalcontinuous part of the oscillation of said shaft.

2. The combination set forth in claim 1 further characterized in thatsaid means includes a member rigidly connected to said shaft, operat ingmembers carried by said latter member in positions onset from the shaftaxis, and gearing connecting said operating members with said concentricadjusting members.

3. The combination set forth in claim 1 further characterized in thatsaid means includes a member fixed to said shaft, a plurality ofoperating elements journalled in said latter memher and offset from theaxis of said shaft, worms carried by said member and adapted to berotate'd respectively by said operating elements. and worm gears securedrespectively tosaid concentric adjusting members whereby rotation ofsaid worms effects adjustment of their respective cam discs.

4. A control apparatus for a hydraulic press comprising, in combination,a shaft, a plurality of cam discs iournalled coaxially of said shaft tohave movementtherewith and each being adiustable relative thereto and toeach other. means for effecting said adiustment'of the cam discsincluding actuating members disposed coaxially of said shaft, a memberfixed to said shaft to move therewith at all times as a continuouslynormal part of the movement thereof, a plurality of operating elementsjournalled in said latter member and oflsetfrom the axis of said shaft.worms carried in said member and adapted to be at right angles to saidworms thereby to indicate the angular position of said cam discs.

5. The combination set forth in claim 1 further characterized in'thatsaid means includes a member fixed to said shaft, a plurality ofoperating elements journalled in said latter member in positions offsetfrom the axis of said shaft,

worms carried by said member and adapted to be rotated respectively bysaid operating elements, worm gears secured respectively to saidconcentric adjusting members whereby rotation of said worms effectsadjustment of their respective cam discs, and. means for oscillatingsaid shaft whereby said cam discs and operating elements oscillatetherewith.

6. A control mechanism for a hydraulic press having a movable memberwhose movement is under the control of hydraulically operated means forwhich fluid is supplied from a pressure fluid source comprising, incombination, means for variably controlling the pressure fluid for thehydraulically operated means, a shaft, a pair of axially spaced camdiscs arranged coaxially of said shaft to be driven thereby, a crossheadfor effecting actuation 'of said variable controlling means and beingdisposed between said discs and having ends extending in oppositedirections from said shaft, means for reciprocably guiding saidcrosshead, and a pair of cam followers mounted on the opposite sides ofsaid crosshead at one end thereof and a third cam follower mounted onone of said sides of the other end of said crosshead whereby the camfollowers at opposite ends of said crosshead but on the same sidethereof are both engageable by one of said cam discs to controlsuccessive portions'of movement of said crosshead in one direction ofmovement thereof and the other cam is engageable with said third camfollower to control movement of said crosshead in opposite direction ofmovement thereof thereby to effect a predetermined movement of saidmovable press member.

v 7. A control mechanism for a hydraulic press comprising, incombination, a press control member having a reciprocable crosshead, anoscillating shaft traversing the plane of reciprocation of saidcrosshead, a cam disc disposed coaxially of said shaft and driventhereby to move said crosshead in one direction, and means forcontrolling the extent of movement of said cross? head in a part of itsmovement including a pivoted arm engageable with said crosshead and a Ascrew and nut operatively connected to said arm to adjust the same.

8. A control mechanism for a hydraulic press comprising, in combination,a press control member having a reciprocable crosshead, an oscillatingshaft traversing the plane of reciprocation of said crosshead. a camdisc disposed coaxially of said shaft and driven thereby to move saidcrosshead in one direction, said crosshead having a slot elongated inthe direction of reciprocation, a pivotal arm extending into said slotto control the extent of movement of said crosshead in a part of itsmovement, and a screw and nut operatively connected to said am foradjusting the same. 7

' PAUL (J. OOH-INS.

